How do I use the quadratic formula to solve $f(x) = 4x^2 + 12x + 9$ ?

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Answer 1 · 2014-09-30T03:19:58

$ax^2+bx+c=0$

$4x^2+12x+9=0$

$a=4, b=12, c=9$

Quadratic formula

$x=(-(12)+-sqrt((12)^2-4(4)(9)))/(2(4))$

$x=(-12+-sqrt(144-144))/8$

$x=(-12+-sqrt(0))/8$

$x=(-12)/8$

$x=-3/2$

$x=-1.5$

How do I use the quadratic formula to solve f(x) = 4x^2 + 12x + 9f(x) = 4x^2 + 12x + 9?